Abstract: When hospital mattresses are to be disinfected or washed, measures must be taken to prevent the washing water from penetrating through the cover to the mattress. These special measures to make closures in the form of e.g. zippers, button closures or snap closures liquid-tight, may be tape or the like. To avoid these difficulties and drawbacks, the closure according to the invention may be constructed as a strip (9), which may be secured directly to the cover (3). Then, the strip (9) and the cover (3) may be cut to form an opening (8) through which the mattress (1) may be inserted. The subsequent closing takes place by means of a slidable strip (6) which may he applied and locked to the first strip (9). The strips (6, 9) are welded together at the ends to form an end closure (7). This results in a strong and liquid-tight closure so that the mattress may be washed/cleaned in a washing machine.

Abstract: The present invention provides methods for pretreating water for desalination. According to one embodiment of the invention, a method for pretreating water is provided comprising simultaneously emitting acoustic energy to cause cavitation and light at a wavelength of 200 nm or less at the water. The light causes ozone to be generated. The ozone acts as an oxidizing and anti-foaming agent to sterilize the water. The ozone also inhibits the amalgamation of soft scales in the water. The inventors have also discovered that this method is more efficient than separately applying the acoustic energy and the light to the water. As a result, this method requires on average 25-30% less energy than separately applying the acoustic energy and light. The ozone is preferably removed or destroyed in the water after this method is performed. The ozone may be destroyed by emitting pulsed light at a wavelength of greater than about 200 nm at the water.

Abstract: A device and method for its use for separating particulate matter into fractional components. The device is characterized as being in the shape of a substantially vertical column having a feed port for feeding the particulate matter thereto. A top is provided for removing a light fraction of the particulate matter and a bottom for collecting a heavy fraction of the particulate matter and a longitudinal axis between the top and bottom portions of the column. Provision is made for drawing current of fluid such as air through the column which contains a channel characterized as having a series of angular bends with respect to the longitudinal axis, the bends being more acute to the longitudinal axis as the distance increases from the feed port.